Improvements, enlargements and extensions to the sewage works system
by the Town or others shall be subject to the approval of the Town Engineer
with regard to design, construction, operation and financing. Where construction
and financing are to be by private organizations, such organizations shall
furnish a maintenance and guaranty bond in the amount of 5% of the estimated
cost of construction and running for a period of one year after completion
of construction and acceptance by the Town. Prior to the approval of the plans
for improvements, enlargements and extensions, said private organizations
shall deposit with the Town a sum equal to 2 1/4% of the estimated cost
of construction to cover inspection costs. Any unused balance of the deposits
remaining after completion and acceptance of the construction shall be refunded.
All sewage works system improvements, enlargements and extensions, whether
installed by a public agency or a private organization, shall conform to the
standards set forth herein:
A.
Sanitary sewers.
(1)
Sanitary sewers shall not be less than eight inches in
diameter and/or of adequate size and capacity to serve their tributary area
on the design basis of 100 gallons of average daily sewage flow per capita
per day contributed by the estimated future tributary population. Also included
shall be a design allowance for groundwater infiltration of 500 gallons per
inch of pipe to provide a minimum velocity of two feet per second or a maximum
velocity of 15 feet per second when said sewer is flowing full and the appropriate
pipe-roughness coefficient is approved by the Superintendent is utilized.
Sanitary sewers shall be constructed of vitrified clay pipe meeting the requirements
of the latest ASTM standards, except as superseded by the requirements of
Specification CSPA 1-63 for standard strength and CSPA 2-63 for extra-strength
VitraChem sewer pipe. The Town reserves the right to specify and require the
encasement of any sewer pipe with concrete or the installation of the sewer
pipe in concrete cradles if foundation and construction conditions are such
as to warrant such protection in the opinion of the Superintendent. Joints
for sanitary sewers of vitrified clay pipe shall be in accordance with ASTM
C425-60T, as amended to the date of installation and all subject to the approval
of the Engineer. The pipe shall be installed according to the manufacturer's
directions and as approved by the Superintendent. Sanitary sewers shall be
of such design and construction that infiltration or exfiltration shall not
exceed 500 gallons per inch of pipe diameter per mile of pipe per day. Leakage
tests shall be conducted by the contractor at his expense, in the presence
of the Superintendent or an authorized inspector. The leakage tests shall
be performed by filling sections of the sewer with water between manholes
and then measuring the rate of loss of water in the upstream manhole. The
details of the method shall be subject to the approval of the Superintendent.
The rate of leakage so determined shall be understood to be the equivalent
of the infiltration specified above.
(2)
Sanitary sewers shall be constructed in strict accordance
with the standard specifications of the American Society for Testing Materials,
designation C12-58T, as amended at date of installation, except as modified
herein.
B.
Right-of-way and highway crossings. Concrete, steel or
corrugated metal pipe of suitable diameters and thickness or tunnel liners
of adequate internal diameter shall be installed for encasement or enclosures
of sanitary sewers to be constructed under all rights-of-way and where directed
by the Superintendent or Town Engineer for the crossing of main highways.
C.
Manholes. Manholes shall be constructed of sewer or concrete
brick, concrete block, concrete or precast concrete, complete with cast-iron
frame and cover and steps, approved by the Town Engineer.
